Let's go beyond the nine dots. If we can match your input with a pattern, why cannot we match a pattern with your input? The following code does this, and the regexp is much more simple and easier to understand: 
$pattern = "123456789";
$str_under_testing = "345678";
print "okay" if ($pattern =~ /^\d*?$str_under_testing\d*$/);

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In reply to Re: Code in regexp by pg
in thread Code in regexp by gjb

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